CCLS - Math: K.NBT.1

Number And Operations In Base Ten
Work With Numbers 11–19 To Gain Foundations For Place Value.
State Standard:
Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decomposition by a drawing or equation (e.g., 18 = 10 + 8); understand that these numbers are composed of ten ones and one, two, three, four, five, six, seven, eight, or nine ones.